Sodium leakage and combustion tests; Measurement and distribution of droplet size using various spray nozzles

not registered ; Hirabayashi, Masaru; not registered; Oki, Shigeo ; not registered; not registered 

In order to develop a numerical code simulating sodium fires initiated frame dispersion of droplets, measured data of droplet diameter as well as its distribution are needed. In the present experiment the distribution of droplet diameter was measured using water, oil and sodium. The tests elucidated the influential factors with respect to the droplet diameter. In addition, we sought to develop a similarity law between water and sodium. The droplet size distribution of sodium using the large diameter droplet (Elnozzle) was predicted. The results are as follows. (1)Verification of existing method to determine droplet size distribution. Using a phase Doppler system the droplet size distribution to water spray from a binary fluid nozzle was measured. We found that there was not a large difference between the measured distribution and Nukiyama-Tanasawa distribution function. (2)Characterization of inferential parameters with respect to droplet size distribution. Here we note that the droplet size distribution using a nozzle with binary fluid was different from the one using a compression nozzle was used. It was clarified that the viscosity and surface tensjon are the primary factors which influence the volumetric average diameter. The correlation equation between droplet diameter containing viscosity and surface tension terms, was derived. (3)Evaluation on the droplet size distribution to sodium spray from the El nozzle. A relationship between the volumetric average diameter and the pressure was studied and the volumetric average diameter was formulated as a function of the physical properties (viscosity, surface tension) in the case of the E1 nozzle. Finally, the droplet size distribution to sodium spray from the E1 nozzle was estimated using the developed correlation equation.